scholarly journals Estimating the contribution of HIV-infected adults to household pneumococcal transmission in South Africa, 2016–2018: A hidden Markov modelling study

2021 ◽  
Vol 17 (12) ◽  
pp. e1009680
Author(s):  
Deus Thindwa ◽  
Nicole Wolter ◽  
Amy Pinsent ◽  
Maimuna Carrim ◽  
John Ojal ◽  
...  
Keyword(s):  
South African ◽  
Hidden Markov ◽  
Age Groups ◽  
Hiv Status ◽  
Older Children ◽  
Markov Modelling ◽  
Household Transmission ◽  
Pneumococcal Carriage ◽  
Immunodeficiency Virus ◽  
Infected Adult

Human immunodeficiency virus (HIV) infected adults are at a higher risk of pneumococcal colonisation and disease, even while receiving antiretroviral therapy (ART). To help evaluate potential indirect effects of vaccination of HIV-infected adults, we assessed whether HIV-infected adults disproportionately contribute to household transmission of pneumococci. We constructed a hidden Markov model to capture the dynamics of pneumococcal carriage acquisition and clearance observed during a longitudinal household-based nasopharyngeal swabbing study, while accounting for sample misclassifications. Households were followed-up twice weekly for approximately 10 months each year during a three-year study period for nasopharyngeal carriage detection via real-time PCR. We estimated the effect of participant’s age, HIV status, presence of a HIV-infected adult within the household and other covariates on pneumococcal acquisition and clearance probabilities. Of 1,684 individuals enrolled, 279 (16.6%) were younger children (<5 years-old) of whom 4 (1.5%) were HIV-infected and 726 (43.1%) were adults (≥18 years-old) of whom 214 (30.4%) were HIV-infected, most (173, 81.2%) with high CD4+ count. The observed range of pneumococcal carriage prevalence across visits was substantially higher in younger children (56.9–80.5%) than older children (5–17 years-old) (31.7–50.0%) or adults (11.5–23.5%). We estimate that 14.4% (95% Confidence Interval [CI]: 13.7–15.0) of pneumococcal-negative swabs were false negatives. Daily carriage acquisition probabilities among HIV-uninfected younger children were similar in households with and without HIV-infected adults (hazard ratio: 0.95, 95%CI: 0.91–1.01). Longer average carriage duration (11.4 days, 95%CI: 10.2–12.8 vs 6.0 days, 95%CI: 5.6–6.3) and higher median carriage density (622 genome equivalents per millilitre, 95%CI: 507–714 vs 389, 95%CI: 311.1–435.5) were estimated in HIV-infected vs HIV-uninfected adults. The use of ART and antibiotics substantially reduced carriage duration in all age groups, and acquisition rates increased with household size. Although South African HIV-infected adults on ART have longer carriage duration and density than their HIV-uninfected counterparts, they show similar patterns of pneumococcal acquisition and onward transmission.

scholarly journals Estimating the contribution of HIV-infected adults to household pneumococcal transmission in South Africa, 2016-2018: A hidden Markov modelling study.

2021 ◽  
Author(s):  
Deus Thindwa ◽  
Nicole Wolter ◽  
Amy Pinsent ◽  
Maimuna Carrim ◽  
John Ojal ◽  
...  
Keyword(s):  
South African ◽  
Hidden Markov ◽  
Age Groups ◽  
Hiv Status ◽  
Older Children ◽  
Markov Modelling ◽  
Household Transmission ◽  
Pneumococcal Carriage ◽  
Immunodeficiency Virus ◽  
Infected Adult

Human immunodeficiency virus (HIV) infected adults are at a higher risk of pneumococcal colonisation and disease, even while receiving antiretroviral therapy (ART). To help evaluate potential indirect effects of vaccination of HIV-infected adults, we assessed whether HIV-infected adults disproportionately contribute to household transmission of pneumococci. We constructed a hidden Markov model to capture the dynamics of pneumococcal carriage acquisition and clearance observed during a longitudinal household-based nasopharyngeal swabbing study, while accounting for sample misclassifications. Households were followed-up twice weekly for 10 months for nasopharyngeal carriage detection via real-time PCR. We estimated the effect of participant age, HIV status, presence of a HIV-infected adult within the household and other covariates on pneumococcal acquisition and clearance probabilities. Of 1,684 individuals enrolled, 279 (16.6%) were younger children (<5 years-old) of whom 4 (1.5%) were HIV-infected and 726 (43.1%) were adults (>=18 years-old) of whom 214 (30.4%) were HIV-infected, most (173, 81.2%) with high CD4+ count. The observed range of pneumococcal carriage prevalence across visits was substantially higher in younger children (56.9-80.5%) than older children (5-17 years-old) (31.7-50.0%) or adults (11.5-23.5%). We estimate that 14.4% (95% Confidence Interval [CI]: 13.7-15.0) of pneumococcal-negative swabs were false negatives. Daily carriage acquisition probabilities among HIV-uninfected younger children were similar in households with and without HIV-infected adults (hazard ratio: 0.95, 95%CI: 0.91-1.01). Longer average carriage duration (11.4 days, 95%CI: 10.2-12.8 vs 6.0 days, 95%CI: 5.6 - 6.3) and higher median carriage density (622 genome equivalents per millilitre, 95%CI: 507-714 vs 389, 95%CI: 311.1-435.5) were estimated in HIV-infected vs HIV-uninfected adults. The use of ART and antibiotics substantially reduced carriage duration in all age groups, and acquisition rates increased with household size. Although South African HIV-infected adults on ART have longer carriage duration and density than their HIV-uninfected counterparts, they show similar patterns of pneumococcal acquisition and onward transmission.

Sleep Disturbances Associated with Age and HIV

2005 ◽  
Vol 96 (2) ◽  
pp. 433-434 ◽  
Author(s):  
David E. Vance ◽  
Joe W. Burrage
Keyword(s):  
Sleep Disturbances ◽  
Age Groups ◽  
Secondary Analysis ◽  
Hiv Positive ◽  
Age Group ◽  
Hiv Disease ◽  
Hiv Status ◽  
Normal People ◽  
Immunodeficiency Virus ◽  
Hiv Negative

Sleep disturbances are common in normal people of several age groups and those with Human Immunodeficiency Virus (HIV) disease. In a secondary analysis of data, 50 HIV-positive and 50 HIV-negative adults between 30 and 65 years old responded to 5 items about sleep. No statistically significant differences by HIV status or age group were found.

scholarly journals Epidemiology of Streptococcus pneumoniae serotypes in children before and after pneumococcal vaccination

2021 ◽  
Vol 6 (4) ◽  
pp. 54-66
Author(s):  
I. N. Protasova ◽  
S. V. Sidorenko ◽  
I. V. Feldblum ◽  
N. V. Bakhareva
Keyword(s):  
Streptococcus Pneumoniae ◽  
Age Groups ◽  
Pneumococcal Vaccination ◽  
Healthy Children ◽  
Pneumococcal Serotypes ◽  
Older Children ◽  
Pneumococcal Carriage ◽  
Serotype Replacement ◽  
High Prevalence ◽  
Before And After

Aim. To investigate how the pneumococcal vaccination affects the distribution of Streptococcus pneumoniae serotypes.Materials and Methods. In 2011-2019, 1,852 healthy children (1,354 aged ≤ 5 years and 480 aged from 6 to 17 years) were examined for the nasopharyngeal pneumococcal carriage. Of them, 539 children were tested before the start of pneumococcal vaccination (2011-2014), while 1,313 were tested during the vaccine campaign (2015-2019). Pneumococcal strains were serotyped using multiplex polymerase chain reaction.Results. Streptococcus pneumoniae serotype distribution considerably differed between children ≤ 5 and 6-17 years of age. Serotypes 23F, 19F, 19A, 6AB, and 15BC were prevalent in children ≤ 5 years of age while the older children were characterised by a high prevalence of capsular serotypes (3 and 33AF/37), serogroup 9 (9AV and 9LN), non-typeable streptococci, as well as 19F, 6AB and 6CD serotypes. Vaccination was associated with a significantly decreased prevalence of Streptococcus pneumoniae carriage (from 41.5% to 19.2%) among children ≤ 5 years of age, while this reduction was less pronounced (from 13.5 to 9.0%) in older children. Vaccination led to the shift in the distribution of pneumococcal serotypes towards an increased prevalence of non-vaccine serotypes that was particularly prominent in children ≤ 5 years of age. In particular, vaccination reduced the prevalence of 23F and 19A pneumococcal serotypes but heightened prevalence of 11AD serotype and to the appearance of previously undetected serotypes such as 8, 10A, 17F, 22F, 24ABF, 34, and 39.Conclusion. Pneumococcal vaccination decreased prevalence of pneumococcal carriage, yet causing a serotype replacement effect requiring improved microbiological monitoring in children of all age groups.

scholarly journals Serotype patterns of pneumococcal disease in adults are correlated with carriage patterns in older children

2019 ◽  
Author(s):  
Anne L. Wyllie ◽  
Joshua L. Warren ◽  
Gili Regev-Yochay ◽  
Noga Givon-Lavi ◽  
Ron Dagan ◽  
...  
Keyword(s):  
Invasive Pneumococcal Disease ◽  
Pneumococcal Disease ◽  
Age Groups ◽  
Deviance Information Criterion ◽  
Information Criterion ◽  
Older Children ◽  
Disease Patterns ◽  
Pneumococcal Carriage ◽  
Age Related ◽  
Carriage Prevalence

ABSTRACTBackgroundThe importance of specific serotypes causing invasive pneumococcal disease (IPD) differs by age. Data on pneumococcal carriage in different age groups, along with data on serotype-specific invasiveness, could help to explain these age-related patterns and their implications for vaccination.MethodsUsing pneumococcal carriage and disease data from Israel, we evaluated the association between serotype-specific IPD in adults and serotype-specific carriage prevalence among children in different age categories, while adjusting for serotype-specific invasiveness. We used a sliding window approach to estimate carriage prevalence using different age groupings. Deviance Information Criterion was used to determine which age groupings of carriage data best fit the adult IPD data. Serotype-specific disease patterns were further evaluated by stratifying IPD data by comorbidity status.ResultsThe relative frequency of serotypes causing IPD differed between adults and children, and also differed between older and younger adults and between adults with and without comorbidities. Serotypes over-represented as causes of IPD in adults were more commonly carried in older children as compared to younger children. In line with this, the serotype-specific frequency of carriage in older children (aged 36-59 months), rather than infants, best correlated with serotype-specific IPD in adults.ConclusionsThese analyses suggest that older children, rather than infants, are the main drivers of disease patterns in adults. These insights could help in optimizing vaccination strategies to reduce disease burden across all ages.40-word summary of the article’s main pointSerotype-specific rates of invasive pneumococcal disease in adults are better correlated with serotype-specific carriage patterns in older children (36-59 months of age) than those in infants.

scholarly journals Tuberculosis, Human Immunodeficiency Virus, and the Association With Transient Hyperglycemia in Periurban South Africa

2019 ◽  
Vol 71 (4) ◽  
pp. 1080-1088 ◽  
Author(s):  
Mmamapudi Kubjane ◽  
Natacha Berkowitz ◽  
Rene Goliath ◽  
Naomi S Levitt ◽  
Robert J Wilkinson ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
South African ◽  
Medical Records ◽  
Hiv Status ◽  
Tb Treatment ◽  
Immunodeficiency Virus ◽  
High Prevalence ◽  
Persistent Hyperglycemia ◽  
Hiv 1

Abstract Background Diabetes mellitus (DM) increases tuberculosis (TB) risk. We assessed the prevalence of hyperglycemia (DM and impaired glucose regulation [IGR]) in persons with TB and the association between hyperglycemia and TB at enrollment and 3 months after TB treatment in the context of human immunodeficiency virus (HIV) infection. Methods Adults presenting at a Cape Town TB clinic were enrolled. TB cases were defined by South African guidelines, while non-TB participants were those who presented with respiratory symptoms, negative TB tests, and resolution of symptoms 3 months later without TB treatment. HIV status was ascertained through medical records or HIV testing. All participants were screened for DM using glycated hemoglobin and fasting plasma glucose at TB treatment and after 3 months. The association between TB and DM was assessed. Results Overall DM prevalence was 11.9% (95% confidence interval [CI], 9.1%–15.4%) at enrollment and 9.3% (95% CI, 6.4%–13%) at follow-up; IGR prevalence was 46.9% (95% CI, 42.2%–51.8%) and 21.5% (95% CI, 16.9%–26.3%) at enrollment and follow-up. TB/DM association was significant at enrollment (odds ratio [OR], 2.41 [95% CI, 1.3–4.3]) and follow-up (OR, 3.3 [95% CI, 1.5–7.3]), whereas TB/IGR association was only positive at enrollment (OR, 2.3 [95% CI, 1.6–3.3]). The TB/DM association was significant at enrollment in both new and preexisting DM, but only persisted at follow-up in preexisting DM in patients with HIV-1 infection. Conclusions Our study demonstrated high prevalence of transient hyperglycemia and a significant TB/DM and TB/IGR association at enrollment in newly diagnosed DM, but persistent hyperglycemia and TB/DM association in patients with HIV-1 infection and preexisting DM, despite TB therapy.

scholarly journals Persistent and Emerging Pneumococcal Carriage Serotypes in a Rural Gambian Community After 10 Years of Pneumococcal Conjugate Vaccine Pressure

2020 ◽  
Author(s):  
Effua Usuf ◽  
Christian Bottomley ◽  
Rebecca Gladstone ◽  
Ebrima Bojang ◽  
Kaddijatou Jawneh ◽  
...  
Keyword(s):  
Randomized Trial ◽  
Pneumococcal Conjugate Vaccine ◽  
Age Groups ◽  
Genomic Analysis ◽  
Cluster Randomized Trial ◽  
Older Children ◽  
Cross Sectional ◽  
Conjugate Vaccines ◽  
Pneumococcal Carriage ◽  
Cluster Randomized

Abstract Background The continuing impact of pneumococcal conjugate vaccines (PCVs) in regions with high pneumococcal transmission is threatened by the persistence of vaccine serotypes (VTs) and the emergence of nonvaccine serotypes (NVTs). Methods In 2016, we conducted a cross-sectional carriage survey (CSS5) in a community where PCV7 was first introduced in 2006 during a cluster-randomized trial conducted before nationwide introduction of PCV7 (2009) and PCV13 (2011). We estimated prevalence of PCV13 VT and NVT by age and compared these with earlier surveys before (CSS0), during (CSS1-3), and after the trial but before PCV13 (CSS4). Genomic analysis was conducted for the nontypeable pneumococci. Results Prevalence of PCV13 VT carriage decreased during the 10 years between CSS0 and CSS5 across all age groups (67.6% to 13.5%, P &lt; .001; 59.8% to 14.4%, P &lt; .001; 43.1% to 17.9%, P &lt; .001; and 24.0% to 5.1%, P &lt; .001, in &lt;2, 2–4, 5–14, and ≥15 years, respectively). However, there was no difference between CSS4 and CSS5 in children ≥2 years and adults (children &lt;2 years, no data). The prevalence of PCV13 NVT increased between CSS0 and CSS5 for children &lt;2 years but decreased in older children and adults. In CSS5, serotypes 3, 6A, and 19F were the most common VT and nontypeable isolates were the most common NVT. Among nontypeable isolates, 73.0% lost the ability to express a capsule. Of these, 70.8% were from a VT background. Conclusions The decrease in PCV13 VT that has occurred since the introduction of PCV13 appears to have plateaued. Significant carriage of these serotypes remains in all age groups.

scholarly journals Serotype Patterns of Pneumococcal Disease in Adults Are Correlated With Carriage Patterns in Older Children

2020 ◽  
Author(s):  
Anne L Wyllie ◽  
Joshua L Warren ◽  
Gili Regev-Yochay ◽  
Noga Givon-Lavi ◽  
Ron Dagan ◽  
...  
Keyword(s):  
Pneumococcal Disease ◽  
A Priori ◽  
Age Groups ◽  
Deviance Information Criterion ◽  
Information Criterion ◽  
Older Children ◽  
Disease Patterns ◽  
Pneumococcal Carriage ◽  
Age Related ◽  
Carriage Prevalence

Abstract Background The importance of specific serotypes causing invasive pneumococcal disease (IPD) differs by age. Data on pneumococcal carriage in different age groups, along with data on serotype-specific invasiveness, could help explain these age-related patterns and their implications for vaccination. Methods Using pneumococcal carriage and disease data from Israel, we evaluated the association between serotype-specific IPD in adults and serotype-specific carriage prevalence among children in different age categories, while adjusting for serotype-specific invasiveness. We estimated carriage prevalence using different age groupings that were selected a priori. The Deviance Information Criterion was used to determine which age groupings of carriage data best fit the adult IPD data. Serotype-specific disease patterns were further evaluated by stratifying IPD data by comorbidity status. Results The relative frequency of serotypes causing IPD differed between adults and children, and also differed between older and younger adults and between adults with and without comorbidities. Serotypes overrepresented as causes of IPD in adults were more commonly carried in older children compared with younger children. In line with this, the serotype-specific frequency of carriage in older children, rather than infants, best correlated with serotype-specific IPD in adults. Conclusions These analyses demonstrate that the serotype patterns in carriage in older children, rather than infants, are best correlated with disease patterns in adults. This might suggest these older children are more influential for disease patterns in adults. These insights could help in optimizing vaccination strategies to reduce disease burden across all ages.

scholarly journals Pediatric household transmission of SARS-CoV-2 infection

2021 ◽  
Author(s):  
Lauren A Paul ◽  
Nick Daneman ◽  
Kevin L Schwartz ◽  
Michelle Science ◽  
Kevin A Brown ◽  
...  
Keyword(s):  
Index Case ◽  
Disease Onset ◽  
Age Groups ◽  
Algorithm Analysis ◽  
Sensitivity Analyses ◽  
Older Children ◽  
Secondary Transmission ◽  
Logistic Regression Models ◽  
Household Transmission ◽  
Index Cases

BACKGROUND: As a result of low numbers of pediatric cases early in the COVID-19 pandemic, pediatric household transmission of SARS-CoV-2 remains an understudied topic. This study sought to determine whether there are differences in the odds of household transmission for younger children compared to older children. METHODS: We assembled a cohort of all individuals in Ontario, Canada with laboratory-confirmed SARS-CoV-2 infection between June 1 and December 31, 2020. The cohort was restricted to individuals residing in private households (N=132,232 cases in 89,191 households), identified through an address matching algorithm. Analysis focused on households in which the index case was aged <18 years. Logistic regression models were fit to estimate the association between age group of pediatric index cases (0-3, 4-8, 9-13, and 14-17 years) and odds of household transmission. RESULTS: A total of 6,280 households had pediatric index cases, and 1,717 (27.3%) experienced secondary transmission. Children aged 0-3 years had the highest odds of household transmission compared to children aged 14-17 years (model adjusted for gender, month of disease onset, testing delay, and average family size: 1.43, 95% CI: 1.17-1.75). This association was similarly observed in sensitivity analyses defining secondary cases as 2-14 days or 4-14 days after the index case, and stratified analyses by presence of symptoms, association with a school/childcare outbreak, or school/childcare reopening. Children aged 4-8 years and 9-13 years also had increased odds of transmission (4-8: 1.40, 95% CI: 1.18-1.67; 9-13: 1.13, 95% CI: 0.97-1.32). CONCLUSIONS: This study suggests that younger children are more likely to transmit SARS-CoV-2 infection compared to older children, and the highest odds of transmission was observed for children aged 0-3 years. Differential infectivity of pediatric age groups has implications for infection prevention controls within households, as well as schools/childcare, to minimize risk of household secondary transmission.

RTS,S/AS01, a vaccine targeting pre-erythrocytic stages of Plasmodium falciparum

2017 ◽  
Vol 1 (6) ◽  
pp. 533-537
Author(s):  
Lorenz von Seidlein ◽  
Borimas Hanboonkunupakarn ◽  
Podjanee Jittmala ◽  
Sasithon Pukrittayakamee
Keyword(s):  
Protective Efficacy ◽  
Age Groups ◽  
Sub Saharan Africa ◽  
Phase Iii ◽  
European Medicines Agency ◽  
Older Children ◽  
Pivotal Phase ◽  
Malaria Epidemiology ◽  
Maximum Benefit ◽  
Sub Saharan

RTS,S/AS01 is the most advanced vaccine to prevent malaria. It is safe and moderately effective. A large pivotal phase III trial in over 15 000 young children in sub-Saharan Africa completed in 2014 showed that the vaccine could protect around one-third of children (aged 5–17 months) and one-fourth of infants (aged 6–12 weeks) from uncomplicated falciparum malaria. The European Medicines Agency approved licensing and programmatic roll-out of the RTSS vaccine in malaria endemic countries in sub-Saharan Africa. WHO is planning further studies in a large Malaria Vaccine Implementation Programme, in more than 400 000 young African children. With the changing malaria epidemiology in Africa resulting in older children at risk, alternative modes of employment are under evaluation, for example the use of RTS,S/AS01 in older children as part of seasonal malaria prophylaxis. Another strategy is combining mass drug administrations with mass vaccine campaigns for all age groups in regional malaria elimination campaigns. A phase II trial is ongoing to evaluate the safety and immunogenicity of the RTSS in combination with antimalarial drugs in Thailand. Such novel approaches aim to extract the maximum benefit from the well-documented, short-lasting protective efficacy of RTS,S/AS01.

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